关键词: α-突触核蛋白, MES23.5细胞, N-甲基-D-天门冬氨酸(NMDA), 细胞毒性

Abstract: Objective To investigate the effect of α-Synuclein(α-Syn) on N-methyl-D-aspartic acid(NMDA)-induced cytotoxicity.Methods NMDA cytotoxicity was produced on MES 23.5 dopaminergic cells.MTS cell viability assay,AO/PI fluorescent labeling of apoptotic cells,and western blot analysis of caspase-3 expression were used for assessment of the NMDA cytotoxicity.Confocal microscopy with Ca²⁺ probe was applied for monitoring the change of intracellular Ca²⁺ concentration.Results NMDA of 5 mmol/L triggered a significant increase of the cell death rate as revealed by decreased cell viability and increased apoptotic cells,which was blocked by a specific NMDA receptor antagonist MK801.In addition,NMDA induced significant increase in caspase-3 expression and intracellular Ca²⁺ concentration.Pretreatment of the cells with α-Syn attenuated the NMDA-induced cell death,[Ca²⁺]i up-regulation and caspase-3 increase.Conclusion α-Syn reduced NMDA-induced cytotoxicity through a mechanism of preventing caspase-3 activation and NMDA-induced Ca²⁺ influx.

Key words: α-Synuclein, MES23.5 dopaminergic cells, N-methyl-D-aspartic acid(NMDA), cytotoxicity